96 bravada front end clunk clunk clunk on accellaration.

I have a 96 bravada with smart track awd. whenever i accellerate all i hear is clunk clunk clunk coming from the front end. Someone told me that it's the transfer case. they said the chain is probably loose and jumping teeth. is this a likely cause for the sound? Can i determine if the chain is loose without dropping the transfer case? if the chain is loose does the whole thing need rebuilt or can i just replace the chain? is it complicated? sorry for so many questions. thanks, Tim

I'd try setting the parking brake with the engine off, transmission in Park, jacking up the drivers side front wheel a few inches, properly set a jack/vehicle stand in case the jack fails then..

turn the tire clockwise & counter-clockwise and look for excessive rotation in the constant velocity joints(both sides) and front differential shaft.
If the joints look like there's no excessive play/slack but the front driveshaft is turning 1/4 turn at the front of the transfercase then excessive transfercase chain/sprocket/bearing wear is suspect.

All help gratefully accepted.